A feature can have one Auxiliary Settings node (

) that contains a collection of various settings for its parent feature that you usually do not need to change.
Auxiliary Settings nodes can be added to the parent
Features nodes under the
Building Blocks branch, or to the features added under a
Physics Interface or
Multiphysics Interface. Right-click the
Auxiliary Settings node to add
Geometric Nonlinearity,
Physics Symbol, and
Usage Condition subnodes.
The Settings window has the following sections:
Enter a valid image file name in the Icon field to use a different icon for the feature. If this field is empty, the feature uses a default icon, which is different depending on the feature’s entity level.
Select the Perturbation method from the list that has the following options:
This setting requires that the Include model input check box in the
Feature node's
Preference section is selected. A model input is by default only shown when a material requests it. In the
Always visible list, add the model inputs that ignore the materials so that they should always appear in the
Settings window of the feature instance.
This section has the settings Enable load groups and
Enable constraint groups which can be selected to make the physics feature compatible with the
Load cases functionality of COMSOL Multiphysics. When load- or constraint groups are enabled for a feature it gets extra menu-items so that the user can select under which group it is active. To make the physics feature useful under load grouping the variables that should be affected by the grouping need to have the
Include in load groups setting selected in the
Variable declaration node. Constraints are by default affected by the constraint grouping. If a particular constraint should not be affected by the grouping, then select the
Exclude from constraint grouping setting in the
Constraint node.
This section contains settings that affect the entities on which the physics feature is applicable. The setting in the Take selection from list controls the maximum selection from which the feature can take its selection. That is the selection that is further restricted by the
Applicable entities setting of the physics feature. The default option,
Parent, means that the selection should be taken from the physics or in the case of a subfeature from the parent feature.
Physics means that the selection should be taken from the physics even in the case of a subfeature. The last option,
Geometry, indicates that the feature should take its selection from the entire geometry.
The other settings are the Not applicable on infinite element domain and
Not applicable on perfectly matched layer domain check box. Select any of these check boxes to make sure that the physics feature cannot be applied on a domain of the particular type.
When any of the base vector systems choices of the parent physics feature are Selected input coordinate system, this section has settings that control the input coordinate system. First, there is a
Coordinate section list with the options
Add coordinate system section (the default) and
Use parent’s coordinate systems section. The latter choice disables all other settings and uses the
Coordinate System Selection section from the parent if there is any. The
Add coordinate system section option adds a
Coordinate System Selection section to the physics feature. It also enables a couple of other settings that control this section. Select the
Only allow orthonormal systems check box to only allow the user to choose between orthonormal systems when selecting the input coordinate system of the feature. In the
Filtering of systems list, choose between the options
Allow boundary systems,
No boundary systems, and
Only boundary systems. Note that the filtering only affects features that live on the boundary geometric entity level.